NANOINDENTATION OF TRABECULAR BONE - COMPARISON WITH UNIAXIAL TESTING OF SINGLE TRABECULA

作者：Jirousek Ondrej^*; Nemecek Jiri; Kytyr Daniel; Kunecky Jiri; Zlamal Petr; Doktor Tomas

来源：Chemicke Listy, 2011, 105: S668-S671.

• trabecular bone
• nanoindentation
• micromechanics
• constitutive modelling

To improve the knowledge about the mechanical properties of trabecular bone and their relationship with the properties of their constituting materials it is necessary to measure the properties at micrometer scale. The published mechanical properties of human trabecular bone vary between 1 GPa and 15 GPa. The cause of this broad discrepancy in results might be in sample preparation, different testing protocols or anisotropy and asymmetry of the micro-samples.
The article deals with a comparison between the properties assessed using nanoindentation and properties measured using uniaxial testing of single trabeculae.
A novel experimental device has been developed which enables to measure single trabeculae in tension and compression with high precision. The strains at the surface of the sample are measured optically using a high-resolution CCD camera. The strain field is evaluated with very precise image correlation algorithm applied to whole surface of the loaded sample.
The mechanical properties measured on micrometersized specimens using both methods (nanoindentation and micro-mechanical testing) are then prescribed to FE model of the trabecula sample. The sample is then loaded according to the experimental procedure. The response of the FE model (stress-strain curve) is compared to results from the tensile test.

• 出版日期2011